The present invention relates to a mobile body communication technology. More particularly, it relates to a circuit and method for notifying a ringer failure, applicable to the mobile body communication technology that is referred to as a wireless local loop (hereinafter called WLL).
A prior art for detecting a ringer failure in a telephone is disclosed in, e.g., JP-A-5-110667. According to the prior art, a ringer signal-generating circuit in an exchanger includes a ringer-generating circuit, a phase control section, a timing control section, an alarm-monitoring section, and a monitoring control section. The ringer-generating circuit produces a ringer signal. The phase control section creates a phase control signal in order to impart a connection timing of the ringer signal to a load that is connected to the ringer signal. The timing control section transmits a ringer-transmitting signal to the load in response to the phase control signal from the phase control section. The alarm-monitoring section monitors any fault in the ringer-generating circuit. The monitoring control section flickers an indication lamp in response to an alarm signal from the alarm-monitoring section. In the above ringer signal-generating circuit, there is provided a ringer signal halt section-detecting circuit for detecting the alarm signal from the alarm-monitoring section only during a period of time in which the phase control signal is transmitted from the phase control section. In addition, while the ringer-transmitting signal is rendered inoperative, the ringer signal halt section-detecting circuit detects any fault developed in the ringer signal-generating circuit, and then outputs the alarm signal.
Another prior art for detecting a ringer failure in a telephone is disclosed. According to this prior art, an alarm is issued without interruption when a signal from a ringer-generating circuit is equal to or less than a predetermined value.
In WLL, when one telephone (calling telephone) calls another telephone (called telephone) that is connected to a subscriber""s wireless terminal equipment, then wireless connection is established from a base station to the terminal equipment through a subscriber""s line, and a call from the calling telephone is transmitted to the terminal equipment through an exchange station. However, when a ringer-generating circuit in the terminal equipment is out of order, then such a failure cannot be known at the calling telephone. Therefore, the calling telephone continues a call. This brings about a problem that both of the base station and the terminal equipment remain connected together by wireless through the subscriber""s line. In this case, another problem arises with the terminal equipment of a type designed to provide a battery-assisted backup action. That is, a battery does not last for a long period of time.
An objective of the present invention is to solve the above-mentioned problems.
Moreover, an objective of the present invention is to provide a circuit and method for notifying a ringer failure, designed to allow the ringer failure in a subscriber""s wireless terminal equipment to be appreciated at a base station, to require monitoring the ringer failure in a ringer-generating circuit only when the terminal equipment receives a call from a calling telephone, and to avoid continuing a call in spite of the presence of the ringer failure.
The objective of the present invention is achieved by a circuit for notifying a ringer failure, applicable to a mobile body communication technology prescribed by a wireless local loop, comprising:
a ringer-generating circuit for producing and then outputting a ringer signal in response to detection of call arrival from a calling telephone;
a control section for controlling call remittance, call arrival, conversation, or call waiting, the control section executing control, in response to call arrival from the calling telephone, to permit the ringer-generating circuit to be oscillated, thereby producing and then outputting the ringer signal, the control section providing further control to permit the ringer signal to be transmitted to a called telephone, thereby causing the called telephone to emit a sound of call arrival, the control section practicing yet further control to permit voice data to be exchanged between a base station and the called telephone when a conversation is held between the calling telephone and the called telephone; and,
a ringer failure-detecting circuit connected to the control section, the ringer failure-detecting circuit notifying the control section of the ringer failure in the ringer-generating circuit when detecting such a failure upon receipt of a call from the calling telephone,
wherein the control section is designed to notify the base station through a wireless line that the ringer failure in the ringer-generating circuit has been detected.
The objective of the present invention is achieved by a circuit for notifying a ringer failure, applicable to a mobile body communication technology prescribed by a wireless local loop, comprising:
a ringer-generating circuit for producing and then outputting a ringer signal in response to detection of call arrival from a calling telephone;
a ringer failure-detecting circuit monitoring a ringer failure in the ringer-generating circuit upon receipt of a call from the calling telephone, the ringer failure-detecting circuit sending out a detection signal when detecting the failure; and,
a control section for executing control, in response to call arrival from the calling telephone, to permit the ringer-generating circuit to be oscillated, thereby producing and then outputting the ringer signal, the control section notifying a base station through a wireless line, when receiving the detection signal from the ringer failure-detecting circuit, that the ringer failure in the ringer-generating circuit has been detect.
The objective of the present invention is realized by a system for notifying a ringer failure in a mobile body communication technology prescribed by a wireless local loop, comprising:
a called mobile body and a base station, both of which are connected together through a wireless line; the called mobile body comprising:
a ringer-generating circuit for producing and then outputting a ringer signal in response to detection of call arrival from a calling mobile body;
a ringer failure-detecting circuit monitoring the ringer failure in the ringer-generating circuit upon receipt of a call from the calling mobile body, the ringer failure-detecting circuit sending out a detection signal when detecting the failure; and,
a control section for executing control, in response to call arrival from the calling mobile body, to permit the ringer-generating circuit to be oscillated, thereby producing and then outputting the ringer signal, the control section notifying a base station through a wireless line, when receiving the detection signal from the ringer failure-detecting circuit, that the ringer failure in the ringer-generating circuit has been detect,
the base station comprising:
a means for notifying the calling mobile body, when the control section advises the base station of the ringer failure in the ringer-generating circuit, that the ringer-generating circuit is precluded from calling the called mobile body.
The objective of the present invention is accomplished by a method for notifying a ringer failure, applicable to a mobile body communication technology prescribed by a wireless local loop, comprising steps of:
controlling call remittance, call arrival, conversation, or call waiting;
executing control, in response to call arrival from a calling telephone, to permit a ringer-generating circuit for generating and then sending out a ringer signal to be oscillated, thereby producing and then outputting the ringer signal; and,
monitoring the ringer failure in the ringer-generating circuit upon receipt of a call from the calling telephone, and then notifying the base station through a wireless line, when detecting the ringer failure in the ringer-generating circuit, that such a failure has been detected.
The present invention as structured above exhibits the following effects:
A first effect is that the ringer failure in the terminal equipment can be recognized at the base station.
A second effect is that there is no need to always monitor the ringer failure in the ringer-generating circuit, and instead such a failure may be monitored only when the terminal equipment receives a call from the calling telephone, with the result that a saving in electric current to be consumed is achievable. In particular, the use of the terminal equipment of a type designed to provide a battery-assisted backup action makes it possible to avoid worthless battery consumption. This effect results from situations in which, only when the terminal equipment receives a call from the calling telephone, the ringer failure-detecting circuit detects and flattens the ringer signal from the oscillation circuit, and further which, when determining that the detected output is equal to or less than a predetermined threshold value, then the ringer failure-detecting circuit judges that the oscillation circuit has been out of order, and subsequently reports such a judgement to the control section.
A third effect is that it is possible to avoid continuing a call in spite of the presence of the ringer failure. This effect results from situations in which, only when the terminal equipment receives a call from the calling telephone, the control section notifies the base station of the occurrence of the ringer failure in response to such a notification from the ringer failure-detecting circuit, and further which the base station subsequently announces the same notification to the calling telephone.